Interactive method and apparatus for tracking and analyzing a golf swing in a limited space with swing position recognition and reinforcement

ABSTRACT

The invention pertains to a method for interactively tracking, analyzing and teaching a correct golf swing using an apparatus consisting of a computer with an attached video camera and a special club shaft attachment that is monitored to determine the progress of a golf swing in real-time. A short simulated golf club with a matching golf ball platform is provided for use in a limited space. Club position is evaluated at all points along prescribed swing plane orbits for accuracy with regard to club shaft angle, club face rotation and swing plane location. Leading guides are provided to aid in correct club movement. Trailing position reinforcement guides permit the student golfer to use his own initiative and timing while receiving real-time corrections relating to club and body motion. Simulated ball flight is determined and applied to golf practice range and golf course activities.

REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part application of the prior application Ser. No. 09/878,447 filed on Jun. 11, 2001.

STATEMENT REGARDING FED SPONSORED R & D

[0002] (none)

REFERENCE TO MICROFICHE APPENDIX

[0003] (none)

BACKGROUND AND FIELD OF THE INVENTION

[0004] This invention relates to a method and apparatus for tracking, analyzing and teaching correct golf club movements that can instantaneously react to video images of golf swings for the purposes of guiding the club, analyzing the swing and predicting the ball flight in a limited space. A short, safe club and a limited area platform with one or more simulated golf balls are used to teach the correct swing plane for a club of any length. Swing position recognition is accomplished by an attachment of one or more colored spheres just below the grip on the club shaft. Swing position reinforcement based upon the recognized step-by-step progress of the golf swing verifies correct body and club position during a computer-provided lesson. Swing position recognition also allows the golfer to watch his or her cutout images swinging at various locations on a background golf course during a simulated golf game.

BACKGROUND AND DESCRIPTION OF PRIOR ART

[0005] A golf swing requires the synchronized actions of more than 80 different muscles in a way that is not particularly intuitive or consistent with the human framework. Focusing on the totality of these various muscle movements surpasses the ability of the conscious mind. This requirement for complex and unnatural muscle movements is the principle reason why golf is considered to be a difficult game to master. Even if one is successful in correctly emulating the precise body movements of a given professional, it is unclear that the club movements that are actually produced are correct for a particular person given his or her physical differences.

[0006] Correct movement of the golf club is the main objective of a golf swing. If the club moves correctly then learning the associated body movements becomes a far easier goal. There are as many swing styles as there are body sizes and shapes, even among professionals, but the objective of each is to move the club in a very similar way.

[0007] Training tools exist that focus on body movements during the golf swing, but none describes or teaches correct club movement in terms of geometric position of the golf club, club head rotation and three dimensional shaft direction at every point of the golf swing. And none performs computer image recognition of the golf club and body position to guide the club movements, analyze the swing and predict the ball flight.

[0008] U.S. Pat. No. 6,159,016 compares video recordings of the body motions of a student to that of an instructor or professional. But these recordings lack interactivity because it is only after the student has completed the exercise that he or she can view comparisons. The computers involved receive and display images but do not recognize or analyze club or body movements. That task is left to the student and/or his or her instructor.

[0009] U.S. Pat. No. 6,126,449 allows a student to swing a club within a body template image of a chosen professional instructor. The computer receives and displays images but does not recognize the student's actual club or body movements, leaving the entire burden of swing analysis to the student and his or her instructor. Because the golf swing analyzer has no awareness of what the student is actually doing once the template is set in motion, there can be no responsive interaction between the student and the device. No effort is made by the above cited patent to systematically describe correct body position as a function of correct golf club movement. Since the motion template of U.S. Pat. No. 6,126,449 progresses through the swing unconditionally in a constant predetermined motion without the benefit of position recognition, the student has no opportunity to initiate motion with position reinforcement being provided by an intelligent process. This invention can neither analyze a golfer's swing nor predict his or her ball flight, nor display a cutout of the golfer's image as he swings on a golf course background.

[0010] U.S. Pat. No. 6,126,449 also requires the student to synchronize his or her activities to the timing provided by the pre-recorded template. The student cannot test or exercise his or her club movements swinging freely back and forth using variable timing as he or she can with swing position recognition and reinforcement.

[0011] In the above noted patent there is an uncertain task in deciding which professional's templates to use. Then attempting to emulate the complex body movements executed by that professional can be very difficult and perhaps of no particular advantage in achieving the club and body movements that are correct for the student, given the physical differences between the student and the professional such as differences in anatomy, physiology, flexibility, and strength.

[0012] U.S. Pat. No. 6,059,668 teaches the effects of club movement by allowing the student to observe a light that shines in both directions along the club shaft generated by a device attached to the golf club shaft. This method does not help the student to know if the geometric location of the club is correct at any point. This method fails to detect very common problems, such as that of the golfer bending his forward arm during the back swing producing a swing whose arc is too narrow yet able to satisfy criteria indicating that the swing is correct.

[0013] With nothing other than a light beam to communicate to the student, the above cited patent lacks the effectiveness and accuracy of image analysis and video presentation. It suffers from not being able to review the analysis of a given swing many times at different speeds. This invention becomes the least effective during the forward swing before impact while the club is making its most rapid movement. During this time the student must interpret the light signals and switch his or her view from the light pointing toward the grip end of the club to that pointing toward the head of the club. This invention is unusable outdoors under bright sunlight and physical adjustments are necessary to the platform that reflects the beam of light when using clubs of different lengths.

[0014] U.S. Pat. No. 5,772,449 discloses a method for simulating a golfer's swing by a two step process that first collects data about a golfer's club and body movements and then feeds the data to a commercially available mechanical simulation package. In the second step, an android computer model attempts to reproduce the golfer's swing for the primary purpose of determining what kinds of clubs are best suited to that golfer. This method is not interactive with the golfer and does not teach or include a pattern of an ideal golf swing as is explained below.

[0015] Prior inventions have used video recordings of the golf swings of various professional golfers for comparison to a student as though they were magic formulas. In fact, many professionals owe their success more to extensive practice than to excellent techniques. Since golf tournaments can be seen on national television every weekend, most of the techniques that amateur golfers would like to learn have become common knowledge and are practiced by most professionals. What is needed is a systematic and effective way to learn and practice these well-known club and body movements. These techniques can be interactively taught by a software program that is capable of running on most personal computers equipped with an inexpensive video camera such as a USB web cam.

[0016] Thus a need exists for an easy to use and inexpensive training system that allows a student to focus precisely on club position and club movement with real-time interactive assistance. When the computer has recognized and analyzed the nature of a particular golf swing problem and its solution, then the presentation to the student is more effective using computer generated graphics and audio methods. Since the computer's recognition software can correlate the club position with the position of the student's body parts, a more focused and systematic approach can be taken by the student to learn to swing correctly. Receiving a quantitative rating based upon the quality of the swing movements and viewing the predicted ball flight makes learning and practicing more enjoyable. When the tracking process is applied to a simulated golf game, the golfer can watch his or her own image swinging on the simulated golf course and then observe the ball in flight and as it lands. He or she can then view a replay or an in depth step-by-step analysis of the previous swing before proceeding.

[0017] A further need exists for analysis while practicing back and forth swings with no predetermined timing. The student should be able to spontaneously perform a sequence of swings without prior planning or setup. For a proficient and experienced golfer, this capability provides effective audio and video feedback during warm-up exercises.

[0018] A still further need exists to effectively analyze the correctness of a golf swing at all points of a golf swing because any incorrect variations can have undesirable consequences. Since normal swing motions occur at a high rate of speed, a student or instructor finds it very difficult to analyze a golf swing in real-time. Previous inventions do not have the benefit of the computer instantaneously recognizing, analyzing, understanding and responding to the motion of the student's golf club and reinforcing the club and body positions. When evaluating the geometric coordinates and angles of a golf club in motion, an experienced professional instructor cannot compete with a computer program that has efficient recognition software.

SUMMARY AND OBJECTS OF THE INVENTION

[0019] The present invention provides a golf swing training method and apparatus that measure a student's swing against a semi-circular back swing plane orbit that is followed by a circular forward swing plane orbit. The locations within these orbits serve as reference points for the computer to recognize the correct club movements and body positions that comprise the ideal golf swing. These swing plane orbits can be further differentiated to describe swing planes with correct three dimensional angles that correspond to the effective club lengths of a short, medium or long club.

[0020] The derivation of these swing plane orbits is based upon analysis of a multiple of swings of many professional golfers. The above noted multiple of swings were superimposed over each other in a synchronized slow motion process that revealed a pattern of an ideal swing that is common to substantially all professional golfers. The pattern showed a semi-circular swing plane orbit for the golfer's hands during the back swing and a separate circular swing plane orbit for the golfer's hands during the forward swing. These swing plane orbits were easily extendable to an area of the club shaft near the golfer's hands. The choice of the location of the club shaft near the golfer's hands as a reference point was also valuable to keep the swing plane orbits as small as possible so the video camera's recognition capabilities are optimized by having the golfer as close to the camera as possible.

[0021] The swing plane orbits are automatically determined while the golfer assumes his or her normal stance by considering the height and other physical characteristics of the golfer. They are further verified by several calibrating movements described below. The swing plane orbital locations form a basis for evaluating club shaft direction, clubface rotation and overall body position during a golf swing. They form the basis for swing position recognition and reinforcement that displays a humanoid pattern that represents the ideal club and body positions.

[0022] A spherical attachment is placed on the shaft below the golf club grip. The attachment is tracked in real time by a software program that receives video camera images. The software program continuously monitors the position of the spherical attachment to determine if the club is in a correct swing plane orbital location.

[0023] Patterns on the attachment are analyzed by the computer recognition software to determine the rotation of the club shaft that corresponds to the position of the clubface at a given swing plane orbit location and the direction of the club shaft.

[0024] In a preferred embodiment, four distinct spheres are used to achieve quality recognition when slow camera speed causes the swinging club image to streak. The solid-color balls determine the club shaft's two-dimensional angle. The ball that is divided in the same direction as the club shaft is viewed to determine club's face rotation. The ball divided perpendicularly to the club shaft, the measured club length and attachment location determine the club shaft's three-dimensional angle for adherence to the ideal swing plane as the camera sees the golfer from his or her frontal view.

[0025] A conventional personal computer control interface such as a mouse or keyboard can be used to select the analysis activities, options and displays. The golfer can also control the sequence of activities and choices during his computer lesson or golf game by moving the club attachment onto a selection button. This feature permits the golfer to make various choices while remaining in his or her normal swing location relative to the limited area platform that is normally about five feet from the camera. The student can use a separate monitor for each display or use multiple windows of a monitor capable of displaying combinations of views simultaneously that may show different views based upon the concurrent use of multiple video cameras.

[0026] An initial calibration requirement helps the golfer to adjust the camera position and to move the limited area platform for consistent ongoing positioning. During and after the calibration, a light meter feature tells the user whether the light level is dark, dim, normal or bright. The light meter reading is accomplished by examining the brightness and gray levels of known colors of the attachment following recognition.

[0027] One display shows the student's image and swing plane orbits plus the correct club shaft direction and clubface rotation at various intervals along the swing plane orbital path.

[0028] Another display shows a blow-up of the region of the spherical attachment to precisely view the student's actual club position at that moment and the relation to the display of the correct club position with respect to the swing plane orbital location, club shaft direction and club head rotation.

[0029] Body movement errors are identified at each swing plane orbital location and illustrated suggestions for corrections are offered. Tempo of the swing is evaluated. A USGA handicap rating is assigned to the swing, the scale for which was determined statistically by a correlation of many golfer's actual handicaps versus their level of correctness of swing. Instant replay of the swing can be done at regular speed or in slow motion.

[0030] Another object and advantage is to display a computer generated humanoid image of the correct body position of the student relative to the current swing plane orbital location of the club attachment. This provides swing position reinforcement to help the golfer achieve correct club and body movement. This is an ideal learning situation since the student golfer takes the initiative rather than being led through each step and receives real-time reinforcement for his motion decisions.

[0031] Another analysis activity places the golfer on a golf course or practice range where the ball flight and distance are predicted based upon the real-time analysis of the swing leading to and following the ball impact position. During these activities, the golfer can see his ball in flight as it travels toward a simulated green. A replay or detailed analysis can be viewed subsequently for any swing. An embodiment of the golf course and practice range activities places a cutout camera image of the golfer onto a simulated golf course or practice range backgrounds. This cutout camera image corresponds to the current position of the club attachment with respect to the ideal swing pattern. As the current position proceeds near the correct positions of the ideal swing pattern, the golfer can see himself or herself swing on the golf course or practice range. In this way, the golfer can combine simulated play and swing analysis.

[0032] An object and advantage is to provide a golf swing analysis and training method that recognizes the club position through the images generated by one or more video cameras to measure and guide club movement at all points of the golf swing. Since a computer program is doing all of the analysis, a professional instructor is not required to be part of the process.

[0033] Another object and advantage is to provide a swing analysis and training method that is simple for the student to execute allowing him or her to focus upon guided movements of the club instead of concentrating on coordinating many unnatural body muscle movements simultaneously.

[0034] Another object and advantage is to provide a swing analysis and training method that quantifies correct club position by geometric location and uses this location as a basis to determine correct club shaft direction, clubface rotation and body position.

[0035] Another object and advantage is to automatically calculate the correct swing orbits for the student based upon his or her physical characteristics and a few calibration movements.

[0036] Another object and advantage is to allow the student to customize his or her swing orbits if the standard swing plane orbits do not work such as if he or she has physical limitations.

[0037] Another object and advantage is to display and measure the precision and correctness of the golf club movements while the student swings freely through swing plane orbits superimposed over the live video image of the student using his or her own timing.

[0038] Another object and advantage is to display and measure the precision of the golf club position and movement during a golf swing using a zoomed blown-up view of the current swing plane orbital focal point showing the swing plane orbit outline, the actual club position and the correct club position.

[0039] Another object and advantage is to evaluate the timing of a complete golf swing.

[0040] Another object and advantage is to quantify a complete golf swing with a USGA handicap rating based upon correctness of the club movement to show progress to the student and to make training more enjoyable.

[0041] Another object and advantage is to predict ball flight in terms of quality, strength, initial direction, trajectory and spin based on club head angle, rotation and speed before and after impact with the golf ball.

[0042] Another object and advantage is to be able to use the golf swing analyzer indoors or outdoors.

[0043] Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0044]FIG. 1 shows a computer monitor displaying a pattern of an ideal golf swing including the golfer standing in front of the monitor;

[0045]FIG. 1A shows a computer monitor outline displaying a pattern of an ideal golf swing using a limited area club and golf ball platform including a plurality of swing plane oribts;

[0046]FIG. 2 illustrates part of the golf club shaft having a signal-emitting sphere attached thereon including club rotation indicia;

[0047]FIG. 2A illustrates part of a real or simulated golf club shaft having signal emitting spheres attached thereon including club shaft 2-dimensional angle indicia, 3-dimensional swing plane indicia, and club shaft rotation indicia;

[0048]FIG. 2B illustrates a simulated golf ball platform and mat that use a single ball to achieve various swing planes corresponding to different club lengths while the golfer moves forward or backward.

[0049]FIG. 2C illustrates a simulated golf ball platform and mat that use a specific ball for each of three swing planes corresponding to different club lengths.

[0050] FIGS. 3A-3K illustrate successive locations of a golf club during a swing;

[0051]FIG. 4 shows the location of the golf club in an actual location and in a projected location;

[0052]FIG. 5 shows a method of calibrating the pattern of an ideal golf swing corresponding to the physical characteristics of a golfer;

[0053]FIG. 6 shows the predicted flight of a golf ball toward the target after impact.

[0054] FIGS. 7A-7D illustrate the method by which the golfer's swing image is displayed in real-time on a simulated golf course as a result of swing position recognition.

[0055] FIGS. 8A-8B illustrate the principle of swing position recognition followed by swing position reinforcement of the correct body and club positions.

[0056] FIGS. 9-9A illustrate the method by which selections are made by the golfer using the club attachment while retaining his swinging location a short distance from the computer. If the golfer is not shown in the course image, then he has a picture-in-picture display to guide the selection process.

[0057]FIG. 10 illustrates the light meter values determined from grayness and brightness levels of known colors of the club attachment.

[0058]FIG. 11 illustrates a golfer watching his predicted golf ball flight during a simulated golf game.

[0059]FIG. 12 illustrates a golfer watching his predicted golf ball flight during a simulated practice range session.

[0060]FIG. 13 illustrates a golfer watching his predicted golf ball flight during a simulated golf lesson.

[0061]FIG. 14 illustrates a golfer being monitored from multiple views using multiple video cameras.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

[0062]FIG. 1 shows a live display of a student golfer who is standing in front of a desktop computer monitor display 2. The student's image as captured by an attached video camera 3 is displayed with his or her ideal swing patterns superimposed as a back swing plane orbit 4 and a forward swing plane orbit 5. The golfer is just beginning his or her back swing as indicated by the position of the spherical attachment 6 to his golf club shaft 7 that has been installed just below the grip 8.

[0063]FIG. 1A shows a live display of a student golfer who is standing in front of a computer monitor display outline 2 corresponding to a close-up, limited space method. The student's image is displayed with ideal swing patterns superimposed as a back swing plane orbit for short irons 23, a back swing plane orbit for medium irons 24, a back swing plane orbit for long irons or woods 25, and a forward swing plane orbit 5. The golfer is just beginning his or her back swing as indicated by the position of the multi-spherical attachment 19 to his or her golf club shaft that has been installed just below the grip 8. A club guide 20 illustrates the correct club position ahead as he or she proceeds. The short club is equipped with a soft but durable club head 21 with a clearly visible face 22. The golfer is standing on a rubber mat 29 that covers and stabilizes a soft but durable limited area platform 28 that supports a soft but durable simulated golf ball 26 on a spring with a protective cover 27.

[0064]FIG. 2 shows an enlarged view of the spherical attachment 6 that has been installed over the golf club shaft 7. The spherical attachment 6 is constructed from lightweight and flexible rubber material that can be slid over the grip 8 but that remains in place on the shaft 7. The surface of the sphere 6 is hard and smooth for maximum reflectivity. The size of the sphere 6 is large enough that shapes and patterns allow the computer to uniquely determine the geometric location of the golf club, the direction of the club shaft and the rotation of the shaft with respect to the clubface yet small enough that it does not degrade or complicate the swing experience.

[0065] The sphere 6 is divided into four equal sized quadraspheres and the spherical attachment of FIG. 3 is installed so that the vertical alignment mark normally placed on a golf shaft 7 by the manufacturer corresponds to the dividing line between the eastern and western hemispheres. When viewing the frontal stance position as in FIG. 1, this dividing line 6 a is entirely visible and parts of each of the quadraspheres are visible to the video camera 3. There is also a dividing line 6 b between the northern and southern hemispheres. These quadraspheres are colored alternating black and white for maximum contrast and best recognition in varying lighting conditions. Bordering the top of the sphere is the grip end polar direction indicator 10 a that is colored white. The club head-end polar direction indicator 9, colored white and black, has a barber pole effect that further verifies the rotation of the club shaft 7. All of these alternating black and white placements on the sphere 6, below the sphere 6 at 9 or above the sphere 6 at 10 a are designed to emit a location signal to be picked up by the video camera 3 for further processing in the computer.

[0066] The computer can efficiently recognize the video camera's 3 image of the spherical attachment in FIG. 2 for instantaneous analysis as to correct orbit location. The color patterns that the video camera 3 produces for the sphere 6 and the polar direction indicators 9 and 10 a are unique for any angle of club shaft rotation and for any three-dimensional club shaft direction.

[0067]FIG. 2A shows an enlarged view of a multi-spherical attachment 30, 31, 32, 33 that has been installed over a real or simulated golf club shaft 7. The multi-spherical attachment is more recognizable when streaking occurs when a camera has a slow frame rate. The multi-spherical attachment is constructed from material that has a porous surface for optimal light signal emission. Pure red, green and blue colors are used for efficient recognition using the RGB color spectrum. The size of the multi-spherical attachment is large enough that shapes and patterns allow the computer to uniquely determine the geometric locations of the golf club, yet small enough that it does not degrade or complicate the swing experience. The attachment is located near the grip so that the golfer can be close to the camera while the multi-spherical attachment remains in camera view at all points of the swing. The 2-dimensional angle of the club shaft is determined by recognition of the locations of the solid-color pattern spheres 30, 32. The rotation of the club face with respect to the club shaft 7 is determined by recognition of the rotation of the pattern of the sphere 33 with a dividing line 34 that is parallel to the club shaft 7. The 3-dimensional angle of the swing plane is determined by recognition of the rotation of the pattern of the sphere 31 with a dividing line 35 that is perpendicular to the club shaft 7.

[0068] A preferred embodiment of the club attachment can use an energy source along with a signal-emitting device to produce an energy enhanced signal 66 that can be tracked more effectively under questionable lighting conditions.

[0069]FIG. 2B shows a golf ball platform that is complementary to the club in FIG. 2A. The correct swing plane is achieved according to the footprints 36 shown on the mat 29. To simulate long club use, such as a driver, the golfer uses footprints 37 farthest away from the ball to achieve the flattest swing plane. Footprints 38 produce a swing plane of medium steepness for mid-irons. Use of footprints 39 result in a steep swing plane to simulate use of a wedge.

[0070] The platform is comprised of a block base 40 attached to thin but strong sheet of poly-carbon plastic 41. A peg 42 that is covered by soft but durable foam material inserts into the block 40. The peg has a spring 43 that protrudes from the peg 42 that is attached to a simulated golf ball 26 that is comprised of soft but durable foam material. The spring 43 is covered by protective rubber 27. A mat 29 lays over a sheet of poly-carbon plastic 41 by means of square hole cut in the mat that allows the rubber mat 29 to fit snugly around the block base 40.

[0071]FIG. 2C shows another embodiment of the golf ball platform that is complementary to the club in FIG. 2A. The correct swing plane for a plurality of club lengths is achieved by standing in a single location on the mat 29 and swinging at the ball that achieves the correct swing plane for the chosen simulated club. To simulate long club use, such as a driver, the golfer uses simulated golf ball 46 to achieve the flattest swing plane. Simulated golf ball 45 produces a swing plane of medium steepness for mid-irons. Use of simulated golf ball 44 results in a steep swing plane to simulate use of a wedge.

[0072] The platform is comprised of a block base 40 attached to thin but strong sheet of poly-carbon plastic 41. A peg 42 that is covered by soft but durable foam material inserts into the block base 40 at an angle of approximately 35 degrees that allows the club head of a short fixed-length club to make contact with the chosen ball to achieve the correct swing plane. The peg has a spring 43 for each ball that protrudes from the peg 42 that are attached to simulated golf balls 44, 45, 46. The spring 43 is covered by protective rubber 47. A mat 29 lays over the sheet of poly-carbon plastic 41 by means of square hole cut in the mat 29 that allows it to fit snugly around the block base 40.

[0073]FIGS. 3A to 3K illustrate representative frames, as displayed on a monitor, of the spherical attachment 6 passing through the semicircular back swing plane orbit 4 and the circular forward swing orbit 5 during a correct swing. The direction of the clubface, that is the club shaft rotation, is determined from the video camera's 3 view of the patterns of the spherical attachment in FIG. 2. The patterns of the sphere 6 and polar direction indicators 9 and 10 a determine the three dimensional direction of the club shaft.

[0074] An imaginary line of infinite length in each direction exists which passes through the ball and the target flag on a golf green. This is referred to as the target line. The approximate two-dimensional space that the club “slices through” during a correct swing is referred to as the swing plane. The angle of the swing plane is most affected by the golfer's normal stance and the length of the golf club he or she is currently using. If the three dimensional direction of the club's shaft 7 as determined by the camera's 3 image of the spherical attachment in FIG. 2 is within the swing plane, the swing is said to be on plane at that moment.

[0075]FIG. 3A shows the initial movement of the spherical attachment of the club in the back swing plane orbit 4. The video camera's 3 view of the sphere 6 verifies to the computer that the sphere 6 is in a correct swing plane orbit location. The image of the spherical attachment further determines that the direction of the club shaft 7 is vertical and on plane and correctly rotated so that the clubface is pointed toward the golf ball and the target. The computer verifies that the golfer's head H is positioned correctly behind the golf ball as determined by the club shaft direction.

[0076]FIG. 3B shows continuation of the sphere 6 in the back swing plane orbit 4. The left shoulder 10 has begun to turn to the golfer's right while the club shaft 7 direction is essentially that of the straight left arm 11. The patterns of the sphere 6 indicate that the club shaft 7 has correctly rotated so the clubface is visible to the video camera 3. The computer verifies that the golfer's head H has correctly moved to the right with the turn of the left shoulder to a position vertically above the inside the golfer's right foot.

[0077]FIG. 3C proceeds along the back swing plane orbit 4. The left arm 11 is pointing in a direction that is 180 degrees away from the target and parallel to the target line. The wrists 12 are partially cocked so that the club shaft 7 forms an approximate 45 degree angle with the direction of the left arm 11. The patterns of the sphere 6 show that the club shaft is still rotated so that the clubface is pointing toward the camera 3. This pattern along with the polar direction indicators show that the grip end of the club is correctly pointing at the golf ball and that the swing is on plane. The computer verifies that the golfer's head 9 has correctly moved to the right with the continued turn of the left shoulder to a position vertically above the outside edge of the golfer's right foot FIG. 3D shows the near completion of the back swing, with the left arm 11 reasonably straight and the club shaft 7 direction approximately 90 degrees past the direction of the left arm 11. The image of the sphere 6 verifies to the computer that the clubface is correctly rotated toward the camera 3 and that the grip end of the club still points along the target line verifying that the swing is on plane. The computer verifies that the golfer's head H has correctly moved to the right with the continued turn of the left shoulder 10 to a position vertically above the outside edge of the golfer's right foot. A very important observation can be made by the computer's software from the video camera image while the spherical attachment is in this swing plane orbital location. Since the edge line of the golfer's left hip 13 is still in the same left-justified location as in the normal stance this verifies that the golfer has correctly rotated his or her upper torso and left shoulder 10 to achieve the correct swing plane orbital position. If the edge line of the left hip 13 had moved to the golfer's right, the computer would recognize that the golfer had made a “reverse pivot”, one of the most common errors for amateur golfers.

[0078]FIG. 3E shows the full completion of the back swing and the left shoulder turn. The sphere 6 has entered the forward swing plane orbit 5. The image of the sphere 6 shows that the clubface is correctly rotated toward the camera 3 and that the swing is on plane. The computer verifies that the golfer's head H is correctly pointed so that he or she can see the ball. Since the edge of the chin line 14 is visible, the golfer's head H is correctly raised to permit the proper left shoulder 10 turn.

[0079]FIG. 3F shows a continuation of the forward swing. The initial phase of the forward swing is characterized by rapid and powerful uncoiling of the left shoulder 10. At the same time the left arm 11 has lowered while the wrists 12 remain cocked with the club shaft 7 in a near vertical position. This movement of the left shoulder 10 has changed the center of the swing circle and consequently defined the circular forward swing plane orbit 5. The image of the sphere 6 verifies to the computer that the clubface is correctly rotated toward the camera 3; that the grip end of the club still points along the target line; and that the swing is on plane. The computer verifies that the edge lines of the golfer's left side and left leg produce an angle 15 that is less than 180 degrees. This indicates that significant hip turn has correctly occurred while the sphere is at this swing plane orbital location.

[0080]FIG. 3G shows that the left shoulder 10 has returned to the original stance position, but the lower body has accelerated its turn while the wrists 12 remain cocked as the right shoulder 16 begins to turn toward the target. The club shaft has not rotated very much during the forward swing as yet as indicated by the patterns of the sphere 6 that indicates the clubface is still facing the camera 3. The club shaft direction as determined by the image of the spherical attachment in FIG. 2 is toward the target and on plane.

[0081]FIG. 3H shows the forward swing after impact as the wrists 12 are un-cocked while the entire body is turning toward the target. As the wrists 12 un-cock, they are also rotating the club shaft 7 so that the clubface is facing the target at impact as determined by the video camera's 3 image of the spherical attachment. The clubface direction shortly after impact is very important in predicting whether the swing achieved a “natural draw”, “duck hook” or “slice”. The sphere's 6 correct forward swing plane orbit 5 location and the golfer's head H positioned behind the golf ball indicate power was generated by the swing at impact. The computer's recognition by use of the patterns of the spherical attachment that the club shaft points to the golfer's right ear is very important at this orbital location.

[0082]FIG. 31 completes the right shoulder turn toward the target as the wrists 12 cock once again to accept the momentum of the swing. Club shaft rotation 7 as determined by the image of the spherical attachment verifies to the computer that the clubface is correctly pointing away from the video camera 3. The sphere 6 continues to show that the swing is on plane. The computer recognizes that the golfer's head position while turned toward the target is essentially in the same location as it is in the golfer's normal stance position verifying that he or she was correctly behind the ball at impact. This position represents a correct “follow through”.

[0083]FIG. 3J completes the forward swing as the club speed decelerates and the entire body turns toward the target. . The sphere 6 continues to show that the swing is on plane. The golfer's head position has moved forward significantly showing that he or she is on balance.

[0084]FIG. 3K shows the “world class finish” position. The golfer's weight has been transferred forward onto his or her left leg and the sphere 6 has dropped from its forward swing orbit 5 to rest on his or her left shoulder.

[0085] The above sequence of moves through FIGS. 3A to 3K represents an ideal swing for all golfers to attain. A student simply stands in front of the camera 3 and tries to emulate the displayed ideal swing. Any deviation from an ideal swing is recognized by the computer that immediately responds with visual and audible feedback or by written instructions displayed on the monitor. Illustrations are also used to notify or prompt the student of correct club and body positions. These immediate responses by the computer in response to images received from the video camera of the golfer's actual club and body movements are indicative of the “interactive” nature of the golf swing analyzer.

[0086]FIG. 4 illustrates interactivity of the golfer with the computer and its display on the monitor. As the golfer moves his club, the computer is able to stay a number of frames ahead and to provide the correct club shaft 7′ direction and club face rotation for the near future step of his or her swing even though the pace of the swing is determined solely by the golfer. Since the computer instantaneously recognizes the current progress of the golfer's swing by the image of the sphere 6, all prompts are interactive and enlightened. Thus in FIG. 4, the present location of the sphere 6 attached to the golf club is shown at about seven o'clock in the semicircular back swing orbit 4 and the displayed future position of the sphere 6′ attached to the club is shown at the ten o'clock position of that orbit. An illustration similar to FIG. 3C can also be displayed as a prompt for the correct future body position that corresponds to the displayed correct future club position as recognized by the sphere 7′.

[0087]FIG. 5 shows the first body adjustment that the student is asked to make to calibrate his or her orbits. The calibration process begins as the computer monitor continues to display messages until the images of the student confirm that he or she has assumed a proper stance at approximately the correct distance from the camera. Once the stance position is correct, a silhouette is drawn on the monitor of the student's stance position along with a highlighted outline of the spherical attachment. The student is asked to make several short calibration movements. He or she is first asked to hold the golf club parallel to the ground while pointing the grip end of the club at the target, shown in FIG. 5. His or her left knuckles should be directly above the right toes with the left arm fully extended and no bend of the left elbow. An animated figure at the bottom of the screen illustrates the correct positions. Once this position is achieved, he or she must hold the club still for two seconds. A message then appears to assume a similar position in the opposite direction, right knuckles over left foot, grip end pointing away from the target. The orbits are then calculated and displayed along with the stance position of the student. The above process allows the software to tailor the orbits to the golfer's height and arm reach based upon images that are interactively achieved and processed in real-time.

[0088] The initial orbits are determined by computing the distance of a line that connects the bottom of the spherical attachment of the club to the top of the golfer's head while in his normal stance. This line can be viewed as the base of two equal right triangles that have 12-degree angles emanating from the bottom of the sphere 6 as their hypotenuse. Each hypotenuse equally divides a circle and is equal to its diameter. The circle to the golfer's right forms the outer edge of the back swing orbit 4 for a right-handed golfer. The other circle forms the outer edge of the forward swing orbit 5. The calibration movements cause the dimensions of the orbits to be adjusted if the spherical attachment does not correctly align with the back swing orbit 4 He or she may choose to display the orbits with or without club shaft and club head position references. The student can swing the club freely back and forth at his or her own speed. As the student attempts to keep the sphere 6 within the orbits, he or she may observe the club shaft direction and clubface rotation guides at orbit locations that properly lead the golfer as shown in FIG. 5. Additionally, the software can freeze the frame on the computer monitor at any orbital location if a club movement error is made and the option is enabled. Various orbital checkpoint locations can be selected corresponding roughly to FIGS. 3B-3J.

[0089] The first evaluation made by the computer software concerns the location of the sphere 6 within the orbits 4 and 5 for each orbital checkpoint. The club shaft direction and the clubface rotation are also checked. Failure of any of the club positions to match the requirements at that checkpoint generates a series of messages and suggestions. The recognition software finds body edges relative to orbit locations using Sobel approximation to determine maximum gradient to check major body part position for each checkpoint and reports irregularities with corrective graphic displays. Timing of the swing is evaluated before and after impact to predict ball flight distance. Club shaft rotation angles and body position as determined by the edge detector are used to predict and display simulated ball flight.

[0090] Instant replay of the swing last analyzed can be done at regular speed or in slow motion. It can also be performed step-by-step through the orbital checkpoints and with or without detailed analysis.

[0091]FIG. 6 illustrates the predicted flight of the ball B toward the target T after the club has passed the impact position I during a swing. The monitor displays the direction, curvature and distance of the predicted flight of the ball B. This prediction is based upon the patterns and timing of the images of the sphere 6 before and after the club passes the impact position and the images of the golfer's body position during impact. This display further reassures the golfer of his or her progress toward achieving the ideal swing.

[0092]FIG. 7A illustrates swing position recognition and reinforcement according to the ideal swing pattern to allow the golfer 1 to watch his or her swing in real-time as it is projected onto a golf course setting 48. When the club attachment 19 is recognized by the computer to be in the initial stance position, a humanoid depiction of the correct club and body positions 49 outlines the camera view of the golfer. A golf course setting 48 is displayed outside the humanoid depiction of the correct club and body positions. The golf course setting 48 is a scene that has a plurality of representations. Each representation shows the single golf course scene with a humanoid depiction cut out for one of a plurality of the correct club and body positions. The course scene with the correct humanoid cutout is placed over the background frame of the golfer 1 as he or she swings and thereby changes the location of the club attachment with respect to the swing plane orbits of the ideal swing pattern.

[0093]FIG. 7B illustrates swing position recognition and reinforcement according to the ideal swing pattern as the recognized location of the club attachment 19 is changed by the golfer 1. The humanoid depiction of the correct club and body positions 49 follows the movement of the club attachment 19 closely and effectively demonstrates to the golfer 1 how accurately he or she is swinging according to the ideal swing pattern.

[0094]FIG. 7C illustrates swing position recognition and reinforcement according to the ideal swing pattern as the golfer 1 is shown in the stance position in an indoor location 50 in front of a video camera 3 but views himself or herself 1 actually in stance position on a real golf course 48. The golfer is using a short, safe club 51 with a simulated club head 21 made of soft but durable material. The short club has a multi-spherical attachment 19 with a club head 21 that is aligned to a simulated golf ball 26 attached to a platform 28 made that is held in place by the mat 29 upon which he or she is standing.

[0095]FIG. 7D illustrates swing position recognition and reinforcement according to the ideal swing pattern as the golfer 1 is shown swinging in an indoor location 50 in front of a video camera 3 but views himself or herself 1 actually swinging on a real golf course 48.

[0096]FIG. 8A illustrates swing position recognition and reinforcement according to the ideal swing pattern. The golfer 1 is shown in the stance position in front of a video camera. A transparent humanoid 52 depiction of the correct club and body position is superimposed over the golfer's image. The transparent humanoid 52 depiction corresponds to the recognized location of the club shaft attachment 19 in the stance position.

[0097]FIG. 8B illustrates swing position recognition and reinforcement according to the ideal swing pattern as the golfer 1 is shown swinging in front of a video camera. A transparent humanoid 52 depiction of the correct club and body position is superimposed over the golfer's 1 image that corresponds to the location of the club shaft attachment 19 recognized as being nearest one of a plurality of swing plane orbit locations.

[0098]FIG. 9 illustrates the use of the club attachment 19 to make selections that control the sequence of activities during swing analysis and simulated golf game play so that the golfer can maintain his original swing stance position. This facilitates a continuum of activities during which he does not have to lay down his golf club. The choice buttons 53, 54, 55, 56 are large so that they can be viewed from a distance and are arranged so that the attachment does not accidentally pass through one to reach another. Since no clicking function is present, as with a computer mouse, the position over the button must be held for a brief time before the choice is registered. The flow only provides choices while no swing is in progress. The golfer's image is changed to be a mirror image during control selections where generally, a normal camera view image is shown during swing tracking.

[0099]FIG. 9A illustrates the use of the club attachment 19 to make a selection as indicated by the choice arrow 58 that controls the sequence of activities during simulated golf game play. Because the scene is a golf course setting 48 not including the golfer 1, a picture-in-picture display 57 of the golfer 1 is used so that he can view the motions of his club attachment 19.

[0100]FIG. 10 illustrates the display on the monitor 2 of a light meter feature, where the light meter 59 reports the ambient lighting properties of the setting based upon the brightness and gray properties of known color patterns of the attachment 19. The color intensity and grayness properties are determined subsequent to initial calibration and after each swing.

[0101]FIG. 11 illustrates the predicted ball flight 60 of a swing as it is translated to a simulation of golf play activity. The golfer 1, having completed a swing that he was able to see performed on the golf course 48 in real time, is watching the ball 61 in flight to the target while viewing the explanations 62 as to the cause of said predicted ball flight 60 are displayed.

[0102]FIG. 12 illustrates the predicted ball flight 60 of a swing as it is translated to a simulation of practice range activity. The golfer 1, having completed a swing that he was able to see performed on the practice range 63 in real time, is watching the ball 61 in flight while viewing the explanations 62 as to the cause of said predicted ball flight 60 are displayed.

[0103]FIG. 13 illustrates the handicap rating 64 of a swing that occurs during a golf lesson activity. The golfer 1, having completed a swing that he saw performed on the monitor 2 in real time while swinging in his home 50, is watching the handicap rating 64 that appears immediately upon completion of the swing. He can subsequently replay and analyze the swing to corroborate the handicap rating. A handicap rating and explanation for the rating are also provided. This rating is based upon a correctness total that is computed at each checkpoint during the detailed analysis. Scoring is based upon correct club position and body position throughout the swing, but with emphasis at key points such as the impact position. The software program estimates a USGA handicap rating for a swing based upon the correctness totals that a golfer with that handicap rating normally achieves.

[0104]FIG. 14 illustrates the golfer 1 being monitored by a video camera 3 primarily from the right side view as indicated by the right side swing plane orbit 65. This figure shows that it is possible to monitor a golfer's swing from different video camera 3 views and also to use one or more cameras concurrently. One or more displays 2 can also be used concurrently.  1 Golfer 33 Vertical split sphere  2 Computer monitor display 34 Vertical dividing line  3 Video camera 35 Horizontal dividing line  4 Back swing plane orbit 36 Footprints  5 Forward swing plane orbit 37 Long club footprints  6 Spherical attachment 38 Medium club footprints  7 Golf club shaft 39 Short club footprints  8 Golf club grip 40 Block base  9 Golf club polar indicator 41 Poly carbonate sheet 10 Left shoulder 42 Peg 11 Straight left arm 43 Spring 12 Wrists 44 Short club ball 13 Left hip 45 Medium club ball 14 Edge of chin line 46 Long club ball 15 Body angle 47 Protective rubber cover 16 Right shoulder 48 Golf course setting 17 Left arm 49 Humanoid outline 18 Left elbow 50 Indoor location 19 Multi-spherical fixture 51 Short safe club 20 Club guide 52 Transparent humanoid 21 Club head 53 choice button 1 22 Club face 54 choice button 2 23 Short backswing 55 choice button 3 24 Medium backswing 56 choice button 4 25 Long backswing 57 Picture in picture display 26 Simulated golf ball 58 Choice arrow 27 Protective cover 59 Light meter 28 Limited area platform 60 Predicted ball flight 29 Mat 61 Ball 30 Solid sphere 62 Ball flight explanation 31 Horizontal split sphere 63 Golf practice range 32 Solid sphere 64 Handicap rating B. Ball 65 Side view of swing orbit F. Ball flight 66 Energy enhanced signal H. Golfer's head 6A. Single sphere vertical I. Impact position dividing line T. Target 6B. Single sphere horizontal W. White section of sphere dividing line 10A. Location signal 

What is claimed is:
 1. An interactive method of tracking and analyzing a golf swing in combination with a computer including the steps of placing a golfer in front of a video camera that is associated with said computer, superimposing a pattern of an ideal golf swing on a display monitor of said computer over the live background images of said golfer, said display monitor being clearly visible to said golfer, inducing said golfer to attempt to emulate said pattern of an ideal golf swing as shown on said display monitor, said computer comparing each of a plurality of sequential images captured by said video camera of said golfer's swing to said pattern of an ideal golf swing and responding to the correctness of said golfer's swing in real time, including the step of placing an attachment on a club shaft of said golfer, said attachment exhibiting a surface having a color pattern thereon that is captured by said video camera and is readily recognizable by said computer, said attachment being instrumental for tracking and analyzing the correctness of said attempt to emulate said pattern of an ideal golf swing, including the step of selecting a golf club from a plurality of golf clubs including real and simulated golf clubs.
 2. The method of claim 1, including the step of controlling said computer to provide audio and visual responses as to the correctness of said golfer's swing in real time according to any progress of said golfer's partial swing, said golfer solely determining said progress.
 3. The method of claim 1, including the step of controlling said computer to update said pattern of an ideal golf swing on said display monitor in real time according to the progress of said golfer's partial swing said golfer solely determining said progress.
 4. The method of claim 1, including the step of including in said pattern of an ideal golf swing, a display of an approximately semicircular swing plane orbit for a back swing and an approximately circular swing plane orbit for a forward swing.
 5. The method of claim 1, wherein said pattern of an ideal golf swing includes a display of a plurality of swing plane orbits corresponding to different club lengths.
 6. The method of claim 5, wherein said pattern of an ideal golf swing includes a display of the correct two dimensional club shaft angles, the correct three dimensional swing plane angles, the correct club shaft rotation angles and the golfer's correct body positions corresponding to a plurality of locations within said swing plane orbits.
 7. The method of claim 1, wherein said tracking and analyzing a golf swing include the step of controlling said computer to independently determine said golfer's club position at any time during said golfer's swing from images captured by said video camera.
 8. The method of claim 1, wherein said tracking and analyzing a golf swing includes the step of controlling said computer to independently determine said golfer's body position at any time during said golfer's swing from images captured by said video camera.
 9. The method of claim 1, wherein said pattern of an ideal golf swing further includes a plurality of leading club guides corresponding to a plurality of swing plane orbit locations.
 10. The method of claim 1, including the step of placing a golfer in front of one or more video cameras to monitor said golfer swinging from a plurality of camera views, said camera views including golfer's front, back, left and right sides.
 11. The method of claim 1, including the step of using and interpreting the brightness and gray properties of known color patterns of said attachment as a light meter reporting the ambient lighting characteristics of the setting.
 12. The method of claim 1, including controlling of said computer by moving said attachment over the location of selection buttons displayed on said display monitor so that said golfer can remain at his or her established swing location with respect to said video camera.
 13. The method of claim 12, including the step of changing said display monitor's image of said golfer to a mirror image to naturalize the process of viewing his or her club motion while making choices.
 14. The method of claim 12, including the step of displaying picture-in-picture to display said golfer as he or she makes selections using said club attachment when the background scene does not otherwise include said golfer.
 15. The method of claim 1, including the step of said computer automatically calibrating said pattern of an ideal golf swing individually for said golfer based upon said golfer's size and said golfer's physical characteristics from images captured by said video camera.
 16. The method of claim 1 including the step of displaying a handicap rating on said monitor level following said attempt to emulate a pattern of an ideal swing, said handicap rating being roughly equivalent the USGA handicap system representing said golfer's skill level.
 17. The method of claim 1 including the step of translating said golf swing into a simulated golf lesson, including the steps of selecting a type of golf club, watching his or her said golf swing in a setting actually in view of said video camera in real-time, watching said golf swing with leading guides and trailing reinforcement guides, replaying said golf swing and analyzing said golf swing step-by-step.
 18. The method of claim 1, including the steps of said computer predicting the ball flight for said golf swing as said golfer's club passes through the impact position and then displaying said predicted ball flight toward a target on said display monitor.
 19. The method of claim 18 including the steps of translating said predicted ball flight into a practice range simulation activity including the steps of selecting a type of club, watching himself or herself swing on said practice range simulation in real-time, watching said predicted ball flight to a plurality of targets, replaying said swing on said practice range simulation and analyzing said swing step-by-step and displaying explanations as to the cause of said predicted ball flight, said explanations include calculations for overall quality and strength of said predicted ball flight, direction of said predicted ball flight, trajectory of said predicted ball flight and spin imparted to the ball during said predicted ball flight with possible results of said spin being straight, draw, fade, hook and slice.
 20. The method of claim 18 including the step of translating said predicted ball flight into a golf play simulation activity including the steps of selecting a golf course, watching said swing on said golf course in real-time, watching said predicted ball flight moving to a plurality of targets, replaying said swing on said golf course and analyzing said swing, said analyzing displaying the step-by-step explanations for said predicted ball flight, said explanations include calculations for overall quality and strength of said predicted ball flight, direction of said ball flight, trajectory of said predicted ball flight and spin imparted to the ball during said predicted ball flight with possible results of said spin being straight, draw, fade, hook and slice.
 21. The method of claim 20 wherein said step of golf play simulation includes the participation of one or more players, said players are participating in a manner that is generally consistent in procedure and scoring with the USGA rules of golf.
 22. A method of teaching a golf swing including the steps of inducing a golfer to initiate movements of a real or simulated golf club according to his or her own timing through a plurality of golf swing positions, subjecting said golf swing positions to swing position recognition by a computer, said computer recognizing the current club position and displaying the correct body and club position interactively that is closest to said current club position, thereby providing position reinforcement.
 23. The method of claim 22 including the step of displaying said correct body and club positions by superimposing a transparent humanoid form of said correct body and club position over said golfer's image in real-time as said golfer swings.
 24. A method of swing image relocation of real-time images of a golfer swinging in a setting that is different from the actual setting, including the steps of placing a golfer in a real location such as his home or office in front of a computer, inducing said golfer to initiate swing movements of a real or simulated golf club according to his or her own timing through a plurality of golf swing positions, subjecting said golf swing positions to swing position recognition by a computer, said computer recognizing the current club position and displaying a limited view of said golfer's image, said limited view being said golfer's image outlined by the current correct body and club position that corresponds to said current club position, and superimposing said limited view of said golfer's real-time swing images over an arbitrary background image such as a golf course setting.
 25. The method of claim 24 including the step of displaying said golfer's image in real-time on said golf course setting, said golfer's image being overlaid by said correct body and club position that corresponds to said current club position, said correct body and club position depicted as a humanoid cutout removed from said golf course scene.
 26. The method of claim 24, including the step of viewing the completeness of said golfer's image being displayed on said arbitrary background to provide a visual measure of the correctness of said golf swing with regard to correct body and club positions.
 27. The method of claim 24, including the step whereby said different setting is made to be partially transparent thereby showing said golfer's entire body and club to some extent during said golf swing while retaining the allusion of said different setting, such as said golf course setting.
 28. An apparatus for interactively tracking and analyzing a golf swing comprising a computer having a display monitor therewith and one or more video cameras for receiving images that are then relayed to said computer, first means for displaying a pattern of an ideal golf swing on said monitor, second means for displaying, by superimposing on said monitor, a golfer's swing attempt to emulate said pattern of an ideal golf swing over said pattern of an ideal swing, means for comparing said first display pattern including means attached to a golf club selected from a plurality of golf clubs including real and simulated clubs, of said golfer for displaying a color pattern recognizable by said computer including a plurality of humanoid depictions that provide position reinforcement corresponding to a plurality of swing plane orbit locations.
 29. The apparatus of claim 28 including means for combining a plurality of said humanoid depictions with alternative background scenery that serve to relocate the real-time display images of said golfer's swing onto a different setting, such as a golf course or practice range.
 30. The apparatus of claim 28 wherein said attachments on said club shaft are comprised of one or more spherical objects that include red, green and blue color patterns for efficient computer processing according to the RGB color spectrum.
 31. The apparatus of claim 28 including means for said attachments on said club shaft to utilize an energy source combined with a light signal emission device, such as a watch battery and laser bulb to enhance swing position recognition.
 32. The apparatus of claim 28 including means for automatically calibrating said pattern of an ideal golf swing individually for said golfer based upon said golfer's size and said golfer's physical characteristics from images captured by said one or more video cameras.
 33. The apparatus of claim 28 including leading guides that consist of swing plane orbits and club position guides that show the correct two dimensional club shaft angle, the correct club shaft rotation with respect to the club face and the correct three dimensional swing plane angle with respect to a plurality of swing plane orbit locations.
 34. The apparatus of claim 28 including trailing guides that are comprised of a transparent humanoid depiction displayed on said monitor providing means for displaying the correct body position and club position guides with respect to a plurality of swing plane orbit locations to thereby provide position reinforcement.
 35. The apparatus of claim 28 wherein said means attached to a club is located just below the club grip to keep the swing arc of said means attached to a club as small as possible for close-up monitoring.
 36. The apparatus of claim 28 wherein said club is a short club that causes the outside reach of the swing arc to be smaller than that of a full-length club thereby making it more suitable for use in an area with limited space.
 37. The apparatus of claim 36 wherein said club is equipped with a club head that is soft for the sake of safety but durable enough for striking a simulated golf ball.
 38. The apparatus of claim 36 including a platform having means for holding one or more simulated golf balls thereon, said platform being complementary in size to said short club for achieving one of a plurality of correct swing plane orbits corresponding to different club lengths in a limited space.
 39. The apparatus of claim 38, including means for attaching said platform to a mat that allows said golfer's body weight to hold said platform in place during and after swing impact of said club with said simulated golf balls.
 40. The apparatus of claim 38, including springs attached to said platform to hold said simulated golf balls for striking by said short club, means for protecting said springs by surrounding said springs by a rubber structure.
 41. The apparatus of claim 38, including means for swinging according to one of a plurality of correct swing plane angles as a result of said golfer choosing to strike one of a plurality of simulated balls while said golfer's position on the mat remains unchanged thereby changing the swing plane angle.
 42. The apparatus of claim 38, including means for swinging according to one of a plurality of correct swing plane angles by choosing to change said golfer's foot placement on the mat thereby changing the swing plane angle while striking a single simulated golf ball. 